An embodiment of the invention relates to management of power consumption in an electronic system, by making adjustments to an operating point of a processor in the system, based on a deadline margin for a real-time demand. Other embodiments are also described and claimed.
Power consumption management in electronic computing systems has become a hot topic, especially with portable systems such as notebook computers that are battery-powered (and hence have a limited supply of energy). As portable systems continue to expand their functions and consume more power, different techniques have been developed to better manage their power consumption, e.g. reduce their power consumption whenever possible.
Manufacturers of a computer system's clocked processor elements, such as a central processing unit (CPU) and a graphics processor (or controller), have built into these elements a mechanism that allows its performance capability or operating point to be adjusted on command. For example, the SpeedStep® technology by Intel Corp., Santa Clara, Calif., allows software that is running in the system to dynamically request a changes in the CPU clock frequency and operating voltage based on factors such as CPU processor utilization, when a power source for the system changes, e.g. from line power to battery. In such an algorithm, a new processor clock frequency is determined by applying a scaling factor to the current or actual frequency. The scaling factor was computed based on the most recent “use” of the processor. For example, if the processor was busy only 25% of the time (while performing a given workload), then the frequency may be gradually scaled down to about 25% of its current value. This reduction will reduce power consumption without compromising the timely completion of the workload, provided of course that the workload does not increase significantly.